Solve Transmission Lines Homework: Coaxial Cable, 1kOhm, 10Ohm

[shivik89]

Homework Statement

can someone help me solving this problem ?
A coaxial cable is driven by a pulse source with internal impedance of
1kohms, 1 V amplitude, square wave with duration of both positive and negative pulse is
800 ns, with negligible rise- and fall-time. The load impedance is 10 ohm.The characteristic ipedance of the coax line is 53 ohms.
Sketch the voltage at the end of the line as function of time for 250 ns.

Homework Equations

The Attempt at a Solution

 

[CWatters]

Sketch the voltage at the end of the line as function of time for 250 ns.

nS or uS?

Forum rules require you to at least make an attempt at a solution.

 

[shivik89]

nS or uS?

Forum rules require you to at least make an attempt at a solution.

Thanks for the reply, can you help. it is asked in ns?I tried calculating the reflection coefficient at the input and output but can't get an idea how the voltage will look like

 

[CWatters]

Ok what happens at the start of the transmission line - think potential divider.

 

[shivik89]

I guess at start.The 1V will be divided between the source resitance of 1 kohms and the characteristic impedance of the cable of 53 ohms. so the forward traveling wave is 53/(1000+53) *1 V ?

 

[CWatters]

Yes so a wave/step up of that magnitude sets off down the cable. What happens when it gets to the other end? And what's the voltage that end until it arrives.